The One Thing That's Holding Back the Heat Pump | Hacker News Reader

The One Thing That's Holding Back the Heat Pump

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14 pointsthelastgallon18 comments

Same problem as all electric technologies have: you're dependent on the grid capacity to provide your service. You can't store electricity as affordably as gas and oil. In an extreme cold spell your grid is now being taxed at a maximum and it's a life or death situation if there is no alternative source of heating fuel.

Heat pumps are awesome as long as you don't critically need heat in a critical situation.

Not all electric heating technologies need the grid.

You can DIY a 2kW solar system and store 10kWh of heat in your water heater. No grid connection required.

https://www.pvh2o.com/faq

This problem isn't unique to heat pumps though. Obviously resistive electric has the same problem, but also gas furnaces are useless if you also need the fan running to distribute air through ductwork.

Gas furnace and resistive electric work everywhere when they work. This isn't true of heat pumps.

They only work in most climates. But it'd be tough using a heat pump around Minneapolis or Moscow when it's -20F for a week. The non-universality of heat pumps is a speed bump in path to use.

There are multiple types of heat pumps. Ground-source heat pumps will work to -30c and beyond[0]. If you buy a cold climate air-source heat pump it will also work to -30c (while a conventional model taps out around -10c). They also provide cooling in summer.

[0]: https://www.cbc.ca/news/science/heat-pump-faq-1.6824634

Yep. We heat our house through Colorado winters (pretty cold, but not really cold) with just a high efficiency heat pump and resistive backup in the air handler. The resistive is rarely needed. This is beside the point though which was that even non-electric heating systems often require electricity to function.

I hope things have changed. 10 years ago when I rented a house with a ground source heat pump each winter was terrible. The frost depth here defined by building code is 60". I imagine that system had been burried much too shallow to be effective.

Which brings me to my point: the colder a region is the further down in the ground you have to dig the more costly that excavation rapidly becomes.

Ground-source heat pumps are not a competitive solution for cold places in terms of up-front cost.

Another choice for cold climates is a cascading heat pump: 2 or 3 heat pumps in series, each with a different working fluid.

Fan is a small load. You could run that from a generator. You wouldn't want to run a heat pump from a generator.

Wouldn't the heat pump and generator do better than burning the same fuel in a gas furnace?

Heat pumps and air conditioners use a similar amount of power. Most states are at >90% air conditioner penetration.

It might be an issue if a large portion of them are using resistive backup heat, but AFAICT most people use fossil fuels for backup heat.

Did the author of this piece take all the money that he worked for and buy other people heat pumps?

The writing style of this article is just awful.

I too didn't read the article because of the pay wall, but I would just like to advocate for the heat pump at least for those in mild climates. I did it DIY-style with the Mr. Cool DIY series. Whole thing was around ~5k for a 18k BTU unit. It looks like the article mentions not enough installers, but the DIY series comes with pre-charged lines so there is no need for specialized equipment to "pump down" the lines or pressure test them. Additionally it counts towards the US tax refund you currently get with it. There was some electrical work done and I think that's the gotcha, I did it myself because I've done minor house wiring before. It wasn't too much to run some Romex in on a dedicated breaker and then out to the heat pump. We had nothing in our tiny 900 square foot house in the way of A/C and were using a bunch of portable space heaters. My electricity bill actually went down from previous years.

For me it’s price. I’d love to make the jump to a heat pump but local quotes are in the $20k range before rebates and credits. This stings when the same hardware can be purchased for a quarter of the price.

I’m all for paying for labor on top of that but 4x the price is a bit crazy.

I always chime on these threads.

We had our entire system replaced about two years ago now. Was around 17k with furnace AND heatpump. I had maybe a half dozen quotes and picked the one that was just above middle of the pack (mind you we had to have it replaced as the system was failing).

We still have oil as backup for really cold days.

I was curious if this was all worth it so have been tracking our electricity and oil spend. We'll break even easily within the next few years compared to if we had just replaced everything with the cheaper stuff (non heatpump). Granted we were oil only for heat so that may not be a fair comparison for where you're at but for us its been a no-brainer.

We did have one quote just over 20k for basically the top of the line system which we were told would have given us more savings and a more comfortable home. I do sometimes wish we went with that (payback would have added some years).

I was given quite the delta, with $14k on the low end to replace our ancient gas furnace and AC with a 80 perfect efficiency gas furnace and standard AC unit, $20k for low end heat pump with gas backup, and as high as $34k for the every feature box checked.

I'm still shopping around and not giving up, it's just disheartening to see such a high markup.

How's the heat pump been working out for you? I'm a fan of electrify all the things (within reason) lately and combining a heat pump with a moderately sized solar system seem like a nice combination.

Honestly? No.

I've build a new home and do heat with heat pumps both the home and sanitary water, it's efficient and effective. In the old home there is only minisplit aircon and classic gas heating. Why? Simply because we can't go all, all-electric at the power level needed in classical homes. Yes, heat pumps are effective, but if you are not in a relatively hot climate heating a classic badly insulated home with electricity still means too much power. We can do for some, we can't for all.

My current home with -18/-25℃ (-0.4/-13℉) absorb 6kW/8kW electricity, and that's enough to have 20℃ inside. The old home in a much mild climate use 24kW thermal methane gas. Here a classic home converted to a air/water heat pump would consume around 12-15kW, only a geothermal one can consume less. It's not sustainable if we ALL do that + cars recharging and so on.

The simple truth is that: if local climate do not go much beyond 4℃/39℉ we can convert also old buildings, as long as in the summer we do not need much to cool during the night, otherwise we need new homes.

This is the very same issue with the new deal at all: it's perfectly feasible in new buildings, it's not in classic ones. We can "upgrade" a bit anything, but only a bit.

Is there any significant difference between a heat pump and an air conditioner vis-a-vis installation? We've installed air conditioners at a ferocious pace, can't air conditioner technicians install heat pumps?

(Article behind paywall, so don't know if it answers the question).

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